How do I avoid Alzheimer's caregiver burnout?

Hello, Both of my parents have Alzheimer's. They live in separate assisted living facilities. My mother is much more independent and able to participate in activities so it is best they remain where they are. My mother lived with my husband and I for 3 years prior to her decline and placement. I have been the full caregiver and decision maker for both of them for the last five years. I am a healthy active 64 year old woman, still working full time at a job I love. My only time to enjoy my own pursuits and loves is on the weekend. I feel obligated to visit my parents every weekend but it is beginning to make me feel stressed as that leaves only one day a week for myself and I still have cleaning, shopping, cooking, etc. to do. I love my parents and want to visit them but I always feel like my life is passing me by and I have little time to pursue my interests and loves! I want to be selfish but my sense of obligation is overwhelming. How do others deal with this? Any advise and help is greatly appreciated.